The invention relates to a device for feeding electrical components to a mounting machine for fitting the components to printed circuit boards.
It is usual to hold the components in belts, which are supplied as wound coils. Where necessary, these coils are put together and lined up in rows in a feed device. Each coil is assigned a suitable feed module, into which the component belt is guided. The feed modules are arranged in rows in the same configuration as the coils and are fixed on a table-like support of the feed device. The mounting machine and the support are provided with interacting centering means which allow the feed modules to be correctly assigned to the mounting machine.
Such a configuration with fixed feed modules requires a mounting machine with an x-y-displaceable mounting head, the pick-up gripper of which can be displaced to the individual pick-up positions of the various feed modules. Since it is desirable for the displacement travel of such a mounting head to be as short as possible, the number of feed modules in a feed device is limited, so that the feed device has to be exchanged relatively often detachably linked to the mounting machine. It can therefore be exchanged, together with the coils and the feed modules, in a single operation, so that the changeover times are correspondingly low.
Hitherto, it has been customary to transport the frame-like feed unit by means of a lifting truck. This makes it possible to lower the table-like support onto a holder of the mounting machine from above and to center it accurately using the centering means.
European reference EP 0 277 732 A discloses a carousel-like feed device, the feed modules of which are held on a table-like support which is mounted so that it can pivot about a vertical axis. The feed device can be moved on wheels. On its vertical side, facing the mounting machine, of the feed device, there are centering means which face in the direction of movement and can be inserted horizontally into corresponding mating centering means on the mounting machine. An adjustment device, by means of which the vertical position of the centering means can be set to the height of the mating centering means on the mounting machine by means of an adjustment screw, is arranged between the wheels and a chassis of the feed device. Since the feed device is able to hold a very large number of coils, the feed device does not have to be changed very often, so that the considerable time involved in the height adjustment is of only minor importance.
Furthermore, German reference DE 85 25 978 U (corresponding to U.S. Pat. No. 4,593,462) discloses a feed device which likewise has horizontally oriented centering means. A holding box for the empty bands is mounted tiltably by means of a toggle-lever drive, in order to be able to free an insertion opening for the bands.